Lightning

As we enter mid-spring and the weather finally begins to warm up a bit, we hope to see a number of thunderstorms in Oregon. Inspiring awe in certain while scaring the trousers off others (but not ME, I’m definitely not scared of lightning. No sir,) it’s no surprise that cultures all over the world associate lightning with deity. But what precisely is it?

During an electrical storm, the top section of the storm clouds has a positive charge and the lower portion has a negative charge. It’s not quite clear how the clouds reach these charges in the first place, but one theory is that different forms of liquid (vapor, water and ice droplets) collide as they rise and fall within a cloud. In the collision, electrons are knocked off of the rising moisture and they collect at the base of the cloud, creating the negative charge. It’s thought that rising moisture then carries a positive charge to the top of the cloud. The charge separation within the cloud is what creates an electric field, the strength of which is related to the amount of charge buildup in the cloud.

The strong ionization causes the atmosphere to begin to break down, allowing for currents to flow in an attempt to neutralize the charge. These currents are known as leaders, and they provide a path through the cloud for the lightning to follow. The first (or stepped) leader does not move easily, but jumps in a jagged fashion. Many leaders form at precisely the exact same time, but the first one to make contact with the floor is the one that gets the lightning.

The entire process is somewhat more complicated, but there you have the basics of how lightning is formed. Lightning is much too powerful for even the best of surge protectors to protect against, and it can reach temperatures of 54,000 °F. An average bolt of lightning carries about 30,000 amps.

Lightning is a complex phenomenon with many exceptions and variations.

For example, do you understand:

If you saw photos of the eruption of Icelandic volcano Eyjafjallajökull that erupted in 2010, you might have seen lightning within the plumes of smoke and thought that they definitely need to be photoshopped. Not so!

There’s still research being conducted to the definitive reason for lightning within the smoke plumes of volcanoes, but the overall consensus involves, of all things, dust. The idea is that dust/smoke/ash particles take little charges which become amplified during the chaos of racing from a volcano. With every collision of one particle with another, the charges become increasingly polarized until lightning is inevitable since the polarization becomes too great for the atmosphere to withstand the flow of electricity. The lightning neutralizes the charge separation, essentially relieving the strain of polarization.

There is another lesser known type of volcanic lightning, however, which happens right at the mouth of the volcano and is much less orderly (not the normal branching, bolting lightning we’re used to seeing), manifesting as jagged sparks probably as the result of a hefty charge within the volcano itself.

How Many Different Types of Lightning There Are?

The answer to this question depends on who you ask, and what you think about a”type” of lightning. The typical classifications are as follows:

Cloud-to-cloud (intercloud, which is lightning moving between separate clouds, and intracloud, that’s lightning moving within the same cloud).

Cloud-to-ground (Less common but more dangerous than cloud to cloud. Cloud-to-ground lightning is more complicated than a simple bolt shooting directly from a cloud, however, and includes charges moving up and down from both the cloud and the ground.

Cloud-to-sky (Also known as sprites, cloud-to-sky lightning occurs in the upper atmosphere. They lack the hot temperatures of different types of lightning, and usually have a reddish-orange hue.)

Lightning is also sometimes further specified as:

Ribbon lightning (Successive strokes of lightning are displaced by wind, resulting in a broadened appearance, almost like a double-exposed photograph ).

Bead lightning (The decay of the luminosity of the bolt of lightning, causing a beaded look. This occurs very quickly and is hard to capture.)

St. Elmo’s Fire This is not really lightning, but often closely associated with it and seen during electrical storms. St. Elmo’s Fire (not to be confused with ball lightning as it often is) is the result of a gap in electric charge. It’s made of plasma (ionized atmosphere that emits a glow) and, while lightning is the movement of power from a charged point, St. Elmo’s Fire is a coronal discharge that sparks up at the place where there’s a drastic difference in charge between the air and an object like the mast of a ship or the steeple of a church. St. Elmo’s Fire is the identical thing that occurs in a fluorescent tube- essentially a constant spark, glowing blue due to the particular mix of air molecules. It might also take on a purple hue.

St. Elmo’s Fire is very tricky to locate accurate images or videos of. Many videos exist which claim to be St. Elmo’s Fire but are actually just static discharge (a frequent occurrence around airplanes in the middle of storms). An easy way to tell the difference is that St. Elmo’s Fire does not look like lightning- rather it emits a continuous glow.

Ball lightning- The most mysterious type of”lightning”, there’s some dispute among scientists as to whether ball lightning really exists. Arc faults along power lines (which appear as large, impossibly bright balls of light) and photographic anomalies are both to blame for the confusion.

How to Stay Safe During a Thunderstorm?

Lightning regularly strikes water, so never go swimming or boating during a storm. If you are in the water when a storm starts, get out of the water as fast as possible.
Lightning strikes will follow anything that conducts electricity, so stay off your mobile telephone in a storm and flip off/unplug your computers. If lightning strikes your house, even the strongest of surge protectors will have a hard time protecting your equipment. (Radio waves do not conduct electricity, so as long as your mobile phone is not plugged into an outlet and you are not standing outside during the storm using the metallic device held to your face, it’s safe to use it. They don’t strangely”attract” lightning more than any other object with metal in it).
Lightning does in fact strike twice (the Empire State building is struck 20-25 times per year), so don’t rely on old adages to your security details.
If you’re caught in a thunderstorm and can’t get inside to security, crouch low to the ground but do not lay flat. Try to keep as much of your body from touching the floor as you can, because you’re in more danger of being injured by currents traveling across the ground after a lightning strike than of being stricken directly by a bolt. Ten seconds equals 2 miles, etc..
Lightning in Mythology

One has only to see an electric storm themselves to understand why so many people have connected lightning and thunder with deity. A few popular myths and legends about lightning:

The Thunderbird common to North American indigenous cultures is said to make thunder by the beating of its wings, and lightning is made by glowing snakes that it conveys or directly from its eyes.
There is a lot more to learn about lightning in all of its various incarnations. It is a stark reminder of the incredible strong forces of nature that surround us on all sides. Regardless of how much we understand about it on a scientific level, we may always be inclined to associate with this unbelievable force with deity.